"Terrorists and extremists have sought to misuse your platforms to spread their hateful messages," she will say. "This Forum is a crucial way to start turning the tide. The responsibility for tackling this threat at every level lies with both governments and with industry."

Rudd earlier told Sky News that the government would consider introducing new laws, but that the forum had the potential to be more influential than legislation.

"Of course, it is just one thing to talk about it, but what we want to see is real action," she said.

She added: "We believe the best way to get this material removed from the internet is to let them show us they are doing it. Of course, we can do legislation, we may yet do legislation, but the most effective way of delivering this outcome that we all want is to have this forum which they can lead on."

The home secretary will also speak with representatives of instant messaging service WhatsApp, which she previously singled out as needing to step up its efforts.

She drew criticism after the attack on Westminster Bridge after saying it was “completely unacceptable” that the government could not read WhatsApp messages protected by end-to-end encryption.

But in an article for the Daily Telegraph ahead of today's meeting, Rudd wrote: "To be very clear - Government supports strong encryption and has no intention of banning end-to-end encryption. But the inability to gain access to encrypted data in specific and targeted instances… is right now severely limiting our agencies' ability to stop terrorist attacks and bring criminals to justice."